Low Profile Plate

ABSTRACT

The present application generally relates to orthopedic systems, and in particular, to systems including independent plates and spacers. A plating system can include a spacer and a plate that is independent from the spacer. A number of locking mechanisms can be provided to secure the plate to the spacer. In some cases, the spacer includes a pair of notches that extend on an outer surface of the spacer. The plate can include a pair of lateral extensions that can engage the notches to secure the plate to the spacer. In other cases, the spacer includes an opening including a pair of inlets. The plate can include an enclosed posterior extension that can be received in the pair of inlets to secure the plate to the spacer.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation-in-part application of U.S. Ser. No. 14/190,948, filed Feb. 26, 2014, which is a continuation-in-part application of U.S. Ser. No. 13/785,434, filed Mar. 5, 2013 and of U.S. Ser. No. 14/085,318, filed Nov. 20, 2013, which is a continuation-in-part application of U.S. patent application Ser. No. 13/785,856, filed Mar. 5, 2013, which is a continuation-in-part of U.S. patent application Ser. No. 13/559,917, filed Jul. 27, 2012, which is a continuation-in-part of Ser. No. 13/267,119, filed Oct. 6, 2011, which claims priority to U.S. Provisional Application 61/535,726, filed on Sep. 16, 2011, the entire contents of which are incorporated by reference.

FIELD OF THE INVENTION

The present application is generally directed to orthopedic systems, and in particular, to systems including plates and spacers.

BACKGROUND

Spinal discs and/or vertebral bodies of a spine can be displaced or damaged due to trauma, disease, degenerative defects, or wear over an extended period of time. One result of this displacement or damage may be chronic back pain. In some cases, to alleviate back pain, the disc can be removed and replaced with an implant, such as a spacer, that promotes fusion. In addition to providing one or more spacers, a plating system can be used to further stabilize the spine during the fusion process. Such a plating system can include one or more plates and screws for aligning and holding vertebrae in a fixed position with respect to one another.

Accordingly, there is a need for improved systems involving plating systems and spacers for spinal fusion and stabilization.

SUMMARY OF THE INVENTION

Various systems, devices and methods related to plating systems are provided. In some embodiments, a spinal system comprises a spacer for inserting into an intervertebral space and a plate configured to abut the spacer. The spacer can include an upper surface, a lower surface and an opening that extends between the upper surface to the lower surface, wherein the spacer further includes a tapered leading end. The plate for abutting the spacer can include a plate body, a first opening formed in the plate body for receiving a first bone screw, a second opening formed in the plate body for receiving a second bone screw, a set screw, and a pair of extensions that extend from the plate body that are configured to engage the spacer. The first opening can angled in an upward direction, while the second opening can be angled in a downward direction. The set screw can be configured to prevent back-out of both the first and the second bone screws, wherein the set screw has a first position whereby the first and second bone screws can be inserted past the set screw and into the first and second openings and a second position following rotation of the set screw whereby the first and second bone screws are prevented from backing out by the set screw. A first bone screw is provided for inserting into the first opening in the plate body, wherein the first bone screw is configured to be inserted into a first vertebral body. A second bone screw is provided for inserting into the second opening in the plate body, wherein the second bone screw is configured to be inserted into a second vertebral body different from the vertebral body.

In other embodiments, a spinal system comprises a spacer for inserting into an intervertebral space and a plate configured to abut the spacer. The spacer can include an upper surface, a lower surface and an opening that extends between the upper surface to the lower surface, wherein the spacer further includes a concave leading end. The plate for abutting the spacer can include a plate body, a first opening formed in the plate body for receiving a first bone screw, a second opening formed in the plate body for receiving a second bone screw, a set screw, and a pair of extensions that extend from the plate body that are configured to engage the spacer. The first opening can angled in an upward direction, while the second opening can be angled in a downward direction. The set screw can be configured to prevent back-out of at least one of the first and the second bone screws, wherein the set screw has a first position whereby at least one of the first and second bone screws can be inserted past the set screw and into at least one of the first and second openings and a second position following rotation of the set screw whereby at least one of the first and second bone screws are prevented from backing out by the set screw. Each of the pair of extensions can include a window that extends along a length of the extension. A first bone screw is provided for inserting into the first opening in the plate body, wherein the first bone screw is configured to be inserted into a first vertebral body. A second bone screw is provided for inserting into the second opening in the plate body, wherein the second bone screw is configured to be inserted into a second vertebral body different from the vertebral body.

In some embodiments, a spinal system comprises a spacer for inserting into an intervertebral space and a plate configured to abut the spacer. The spacer can include an upper surface, a lower surface and an opening that extends between the upper surface to the tower surface. The plate for abutting the spacer can include a plate body, a first opening formed in the plate body for receiving a first bone screw, a second opening formed in the plate body for receiving a second bone screw, a set screw, and a pair of extensions that extend from the plate body that are configured to engage the spacer. The first opening can angled in an upward direction, while the second opening can be angled in a downward direction. The set screw can be configured to prevent back-out of at least one of the first and the second bone screws, wherein the set screw has a first position whereby at least one of the first and second bone screws can be inserted past the set screw and into at least one of the first and second openings and a second position following rotation of the set screw whereby at least one of the first and second bone screws are prevented from backing out by the set screw. Each of the pair of extensions can include a window that extends along a length of the extension. A first bone screw is provided for inserting into the first opening in the plate body, wherein the first bone screw is configured to be inserted into a first vertebral body. A second bone screw is provided for inserting into the second opening in the plate body, wherein the second bone screw is configured to be inserted into a second vertebral body different from the vertebral body. The spacer and the plate are independent from one another such that the spacer can be inserted into a desired spinal location prior to abutting the spacer with the plate.

BRIEF DESCRIPTION OF TUE DRAWINGS

FIGS. 1A-1D illustrate different views of a low profile plate attached to a spacer according to some embodiments.

FIGS. 2A-2D illustrate different views of the low profile plate shown in FIGS. 1A-1D.

FIGS. 3A-3D illustrate different views of a PEEK spacer to be used with the low profile plate shown in FIGS. 2A-2D.

FIGS. 4A-4D illustrate different views of an allograft spacer to be used with the low profile plate shown in FIGS. 2A-2D.

FIGS. 5A-5D illustrate different views of a second alternative embodiment of a tow profile plate attached to a spacer according to some embodiments.

FIGS. 6A-6D illustrate different views of the low profile plate shown in FIGS. 5A-5D.

FIGS. 7A-7D illustrate different views of a PEEK spacer to be used with the low profile plate in FIGS. 6A-6D.

FIGS. 8A-8D illustrate different views of an allograft spacer to be used with the low profile plate in FIGS. 6A-6D.

FIGS. 9A-9D illustrate different views of a third alternative embodiment of a low profile plate attached to a spacer according to some embodiments.

FIGS. 10A-10D illustrate different views of the low profile plate shown in FIGS. 9A-9D.

FIGS. 11A-11D illustrate different views of a fourth alternative embodiment of a low profile plate attached to a spacer according to some embodiments.

FIGS. 12A-12D illustrate different views of the low profile plate shown in FIGS. 11A-11D.

FIGS. 13A-13D illustrate different views of a multi-piece allograft spacer to be used with the low profile plates discussed above according to some embodiments.

FIGS. 14A-14D illustrate different views of an alternative multi-piece allograft spacer to be used with the tower profile plates discussed above according to some embodiments.

FIGS. 15A-15D illustrate different views of an alternative low profile plate attached to a spacer according to some embodiments.

FIGS. 16A-16D illustrate different views of a low profile plate shown in FIGS. 15A-15D.

FIGS. 17A-17C illustrate different views of a spacer shown in FIGS. 15A-15D.

FIGS. 18A-18D illustrate different views of another alternative low profile plate attached to a spacer according to some embodiments.

FIG. 19 illustrates a lordotic version of the low profile plate and spacer shown in FIGS. 18A-18D.

FIGS. 20A-20D illustrate different views of another alternative low profile plate attached to multiple spacers according to some embodiments.

FIGS. 21A and 21B illustrate different views of another alternative low profile plate attached to multiple spacers according to some embodiments.

FIG. 22 illustrates another alternative low profile plate attached to multiple spacers according to some embodiments.

FIG. 23 illustrates another alternative low profile plate attached to multiple spacers according to some embodiments.

FIGS. 24A-24C illustrate another alternative low profile plate attached to a multi-piece spacer having three pieces according to some embodiments.

FIGS. 25A and 25B illustrate another alternative low profile plate attached to a multi-piece spacer having a metal insert according to some embodiments.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

The present application is generally directed to orthopedic systems, and in particular, to systems including plates and spacers.

The present application discloses orthopedic plating systems that can be used in spinal surgeries, such as spinal fusions. The plating systems disclosed herein include a plate and a spacer that are independent from one another. In some cases, the plate and the spacer can be pre-attached to one another before positioning them in a desired location of the spine. In other cases, the spacer can first be inserted into a desired location of the spine, and then the plate can be inserted thereafter. Advantageously, the plating systems disclosed herein are of low-profile. For example, they can provide a very small, anterior footprint cervical plate solution for fusion procedures. One skilled in the art will appreciate that while the plating systems can be used with cervical procedures, the plating systems are not limited to such areas, and can be used with other regions of the spine.

FIGS. 1A-1D illustrate different views of a plating system comprising a low profile plate attached to a spacer according to some embodiments. The plating system 5 includes a spacer 10 attached to a low-profile plate 50. Advantageously, the plating system 5 can be inserted through an anterior approach into a spine, and can desirably provide a small anterior footprint.

The spacer 10 is configured to have an upper surface 12, a lower surface 14, and a leading end 22. In some embodiments, the upper surface 12 and/or lower surface 14 includes texturing 16, such as teeth, ribs, ripples, etc. to assist in providing frictional contact with adjacent vertebral bodies. In some embodiments, the leading end 22 of the spacer 10 can be slightly tapered, as shown in FIG. 1A. With the taper, the leading end 22 can serve as a distraction surface that helps the spacer to be inserted into an intervertebral space. As shown in FIG. 1B, the leading end 22 can be concave, though in other embodiments, the leading end 22 can be straight or convex.

The spacer 10 can be substantially C-shaped (as shown in FIG. 3B), whereby it includes two side arms 13 that surround an inner opening 20. Adjacent the side arms 13 is a convex wall 19. In some embodiments, the convex wall 19 is substantially parallel to the concave surface of the leading end 22. The opening 20, which is configured to receive natural or synthetic graft material therein to assist in a fusion procedure, has an open side that is opposite convex wall 19, thereby giving the spacer 10 its C-shape.

The spacer 10 has a number of unique features that accommodate the attachment of a plate 50 thereto. Each of the side arms 13 of the spacer 10 includes a notch 17 (shown in FIG. 3B) for receiving a corresponding protrusion 71 of a lateral arm or extension 70 of the plate 50, thereby advantageously forming a first locking mechanism between the spacer 10 and the plate 50. In addition, in some embodiments, each of the side arms 13 of the spacer 10 can also include a hump region 26 (shown in FIG. 3B) that can extend in part into a window 72 of an attached plate 50 (shown in FIG. 2A), thereby advantageously providing a second locking mechanism between the spacer 10 and the plate 50. Advantageously, by providing secure first and second locking mechanisms between the spacer 10 and the plate 50, the plate and spacer will be kept securely together during any type of impaction of the plating system within the body. Furthermore, each of the side arms 13 of the spacer 10 can include a cut-away portion or chamfer 18, 19 (shown in FIG. 3C) to advantageously accommodate screws which pass through the plate. In embodiments that involve a pair of screws through the plate 50—one of which passes in an upward direction, and the other of which passes in a downward direction—one side arm 13 of the spacer 10 will include an upper chamfer 18 formed on an upper surface to accommodate the upwardly directed screw, while the second side arm 13 of the spacer will include a lower chamfer 19 formed on a lower surface to accommodate the downwardly directed screw.

The spacer 10 can be formed of any material. In some embodiments, the spacer 10 is formed of a polymer, such as PEEK, as shown in FIG. 3A. In some embodiments, the spacer 10 is formed of allograft bone, as shown in FIG. 4A. In some instances, to form an allograft implant, allograft bone may be cut or shaved from a desired bone member. The cut allograft bone will then be assembled together, using an adhesive or mechanical fastener (e.g., bone pins). Accordingly, in some embodiments, an allograft spacer 10 is formed of two, three, four or more layers that are assembled together, such as by one or more bone pins. One particular advantage of the invention is that the plate 50 can work with a variety of different spacers 10, as the plate 50 is independently removable from and attachable to the spacer 10. Regardless of whether a surgeon chooses to implant an allograft spacer or PEEK spacer 10 into an intervertebral space, the surgeon can simply attach the low-profile plate 50 to the spacer 10 following implantation into the intervertebral space.

The plate 50 is configured to have a plate body and a pair of lateral extensions 70 that extend from the plate body, each of which has a protrusion 71, for inserting into a corresponding notch 17 of the spacer 10. These lateral extensions 70 help form the first locking mechanism between the plate 50 and the spacer 10, as discussed above. In addition, the lateral extensions 70 of the plate 50 each include a window 72 (shown in FIG. 2A) for receiving a hump region 26 on the arms 17 of the spacer 10, thereby helping to form the second locking mechanism between the plate 50 and the spacer 10, as discussed above.

In addition to attaching to the spacer 10, the plate 50 is also configured to attach into one or more vertebral bodies via one or more bone screws. As shown in FIG. 1A, the plate 50 includes a first screw hole 52 and a second screw hole 54 for receiving bone screws therein. In some embodiments, screw hole 52 is angled upwardly such that an inserted bone screw passes upward into an upper vertebral body, while screw hole 54 is angled downwardly such that an inserted bone screw passes downward into a tower vertebral body. White the illustrated embodiment illustrates a pair of screw holes for receiving a pair of bone screws, it is possible to have one, three, four, five or more screw holes for receiving a different number of bone screws.

Over time, it is possible for bone screws to back-out. The plate 50 thus has a blocking or set screw 56 (shown in FIG. 1C) that assists in preventing back-out of inserted bone screws. As shown in FIG. 1C, the set screw 56 can be in an initial position that allows first and second bone screws to pass through holes 52, 54. Once the bone screws have been inserted through the holes 52, 54, the set screw 56 can be rotated (e.g., 90 degrees), to thereby block the bone screws and prevent back out of the bone screws. In some embodiments, the set screw 56 abuts a side of the head of the bone screws to prevent back-out of the bone screws, while in other embodiments, the set screw 56 rests over a top of the head of the bone screws to prevent back-out of the bone screws. In some embodiments, the set screw 56 comes pre-fixed with the plate 50. As shown in FIG. 1C, a single set screw 56 can be used to conveniently block a pair of bone screws. In other embodiments, each bone screw can be assigned its own set screw, which can operate independently of one another, to prevent back-out of the bone screw.

The plate 50 can also include one or more knife-like edges 63 that provide additional torsional stabilization when the plate 50 rests against a bone member. As shown in FIG. 1C, the knife-like edges 63 can be formed on both the upper and lower surfaces of the plate 50 body. While the illustrated embodiment shows a pair of knife-like edges 63 on an upper surface of the plate body and a pair of knife-like edges 63 on a lower surface of the plate body, one skilled in the art will appreciate that a different number of knife-like edges 63 can be provided.

FIGS. 2A-2D illustrate different views of the low profile plate shown in FIGS. 1A-1D. From these views, one can see the pair of lateral extensions 70 that extend from the body of the plate 50. At the distal end of each of the lateral extensions 70 is an inwardly-facing protrusion 71 that is configured to fit into a corresponding notch in the spacer 10. In addition, from these views, one can see the windows 72 that are formed in each of the lateral extensions 70. The windows 72 advantageously receive hump regions 26 of the spacer to provide a locking mechanism, and also help to improve desirable radiolucency. Advantageously, the windows 72 can have rounded edges to accommodate the spacer 10 therein. While the illustrated windows 72 are shown as rectangular with rounded edges, in other embodiments, the windows 72 can have a different shape, such as circular or oval. In some embodiments, the plate 50 is assembled axially to the spacer 10.

In some embodiments, the low profile plate 50 can also include indented gripping sections 73 (shown in FIGS. 2A and 2B). These indented gripping sections 73 advantageously provide a gripping surface for an insertion instrument, thereby facilitating easy delivery of the plate to a spacer body during surgery.

FIGS. 3A-3D illustrate different views of a PEEK spacer to be used with the low profile plate shown in FIGS. 2A-2D. From these views, one can see how the spacer 10 a includes an upper surface 12 a and a lower surface 14 a with texturing 16 a; a generally C-shaped body including a pair of arms 13 a each having a notch 17 a formed therein and an upper chamfer 18 u or lower chamfer 19 a; and a tapered leading edge 22 a. In addition, one skilled in the art can appreciate the substantially symmetric shape of the inner opening 20 a, which serves as a graft hole for receiving graft material therein.

FIGS. 4A-4D illustrate different views of an allograft spacer to be used with the tower profile plate shown in FIGS. 2A-2D. While the allograft spacer 10 b shares similar features to the PEEK spacer 10 a shown in previous figures, such as the notches 17 b, hump surfaces 26 b, and chamfers 18 b,19 b, the allograft spacer 10 b need not be the same. For example, the shape of the graft opening 20 b can be more of an arch, as shown in FIG. 4B.

FIGS. 5A-5D illustrate different views of a second alternative embodiment of a low profile plate attached to a spacer according to some embodiments. Rather than having a plate 50 with lateral extensions 70 that extend around the outer surface of a spacer 10, the present embodiment of the plating system 105 includes a plate 150 with an enclosed posterior extension 155 that fits within the body of the spacer 110. The enclosed posterior extension 155 includes extending surfaces 166, 167 that are fitted into corresponding inlets 121, 123 formed in the body of the spacer 120, thereby forming a first locking mechanism between the plate 150 and the spacer 110. In addition, the enclosed posterior extension 155 of the plate 50 includes one or more deformable locking tabs 160 (shown in FIG. 6B) that securely lock into tab holes 181 a in the spacer body 110, thereby forming a second locking mechanism between the plate 150 and the spacer 110. While in some embodiments, the plate 150 can be attached to the spacer 110 after inserting the spacer 110 into a desired location in the body, in other embodiments, the plate 150 can be pre-assembled with the spacer 110 prior to inserting the plating system 105 into the desired location.

Like the spacer 10 in FIG. 1A, the spacer 110 is configured to have an upper surface 112, a tower surface 114, and a leading end 122. In some embodiments, the upper surface 112 and/or lower surface 114 includes texturing 116, such as teeth, ribs, ripples, etc. to assist in providing frictional contact with adjacent vertebral bodies. In some embodiments, the leading end 122 of the spacer 110 can be slightly tapered, as shown in FIG. 7D. With the taper, the leading end 122 can serve as a distraction surface that helps the spacer 110 to be inserted into an intervertebral space. As shown in FIG. 1B, the leading end 122 can be concave, though in other embodiments, the leading end 122 can be straight or convex.

The spacer 110 can be substantially C-shaped (as shown in FIG. 7B), whereby it includes two side arms 113 that surround an inner opening 120. Adjacent the side arms 113 is a straight wall 119 that forms the border of the graft opening 120. The straight wall 119 can include one or more tab holes 181 (shown in FIG. 7A) for receiving deformable tab locks 160 therein. The graft opening 20, which is configured to receive natural or synthetic graft material therein to assist in a fusion procedure, has an open side that is opposite the straight wall 119, thereby giving the spacer 110 its C-shape.

In some embodiments, the graft opening 120 (shown in FIG. 7B) has a different shape from the opening 20 of the spacer 10 of the prior embodiment, as the graft opening 120 is configured to not only receive graft material, but also the enclosed posterior extension 155 of the plate 150. For example, the graft opening 120 includes two inlets—a first inlet 121 formed at the junction between the first arm 113 and wall 119 and a second inlet 123 formed at the junction between the second arm 113 and wall 119 (shown in FIG. 7B)—for receiving outwardly extending surfaces 166, 167 of the plate 150 (shown in FIG. 6B). In addition, the graft opening 120 includes two outwardly tapering walls 111 that provide enough space to accommodate any bone screws inserted in the plate 150. As such, additional chamfers 18, 19 (as shown in FIG. 313) are optional.

Like spacer 10, the spacer 110 can be formed of a variety of materials. In some embodiments, the spacer 110 comprises PEEK, as shown in FIG. 7A, while in other embodiments, the spacer 110 comprises allograft bone, as shown in FIG. 8A.

The plate 150 is configured to have a plate body, and an enclosed posterior extension 155 that extends from the plate body, which is received within and retains the spacer 110. The enclosed posterior extension 155 includes first and second outwardly extending surfaces 166, 167 that fit into inlets 121, 123 formed within the spacer 110 body to form a first locking mechanism. In addition, one or more deformable tab locks 160 extend from an exterior surface of the enclosed posterior extension 155 and are received in corresponding tab holes 181 in the spacer 150 to form a second locking mechanism. In some embodiments, the side walls of the enclosed posterior extension 155 can include one or more windows 172 (shown in FIG. 6A) for improving radiolucency of the plating system. In some embodiments, the plate 150 is assembled axially to the spacer 110.

In addition to attaching to the spacer 110, the plate 150 is also configured to attach into one or more vertebral bodies via one or more bone screws 88, 89. As shown in FIG. 5A, the plate 150 includes a first screw hole 152 and a second screw hole 154 for receiving bone screws 88, 89 therein. In some embodiments, screw hole 152 is angled upwardly such that an inserted bone screw 88 passes upward into an upper vertebral body, while screw hole 154 is angled downwardly such that an inserted bone screw 89 passes downward into a lower vertebral body. While the illustrated embodiment illustrates a pair of screw holes for receiving a pair of bone screws, it is possible to have one, three, four, live or more screw holes for receiving a different number of bone screws.

Over time, it is possible for bone screws to back-out. The plate 150 thus has a blocking or set screw 156 (shown in FIG. 5C) that assists in preventing back-out of inserted bone screws, As shown in FIG. 5C, the set screw 156 can be in an initial position that allows first and second bone screws to pass through holes 152, 154. Once the bone screws have been inserted through the holes 152, 154, the set screw 156 can be rotated (e.g., 90 degrees), to thereby block the bone screws and prevent back out of the bone screws. In some embodiments, the set screw 156 abuts a side of the head of the bone screws to prevent back-out of the bone screws, white in other embodiments, the set screw 156 rests over a top of the head of the bone screws to prevent back-out of die bone screws. In some embodiments, the set screw 156 comes pre-fixed with the plate 150. As shown in FIG. 5C, a single set screw 156 can be used to conveniently block a pair of bone screws. In other embodiments, each bone screw can be assigned its own set screw, which can operate independently of one another, to prevent back-out of the bone screw.

The plate 150 can also include one or more knife-like edges 163 that provide additional torsional stabilization when the plate 150 rests against a bone member. As shown in FIG. 5C, the knife-like edges 163 can be formed on both the upper and lower surfaces of the plate 150 body. While the illustrated embodiment shows a pair of knife-like edges 163 on an upper surface of the plate body and a pair of knife-like edges 163 on a lower surface of the plate body, one skilled in the art will appreciate that a different number of knife-like edges 163 can be provided.

FIGS. 6A-6D illustrate different views of the low profile plate shown in FIGS. 5A-5D. From these views, one can see the enclosed posterior extension 155 that extends from the body of the plate 150. At the distal end of the enclosed posterior extension 155 are a pair of outwardly extending surfaces 166, 167 that are configured to fit within inlets 121, 123 formed in the spacer. From these views, one can also see the deformable tab lock 160 (FIG. 6B) that can help secure the plate 150 to the spacer 110. In addition, from these views, one can see the windows 172 that are formed in each of the arms of the enclosed posterior extension 155. The windows 172 advantageously help to improve desirable radiolucency, and are of large size to provide a large viewing surface area. While the illustrated windows 172 are shown as triangular with rounded edges, in other embodiments, the windows 172 can have a different shape, such as circular or oval. In some embodiments, the plate 150 is assembled axially to the spacer 110.

In some embodiments, the low profile plate 150 can also include indented gripping sections 173 (shown in FIGS. 6A and 6B). These indented gripping sections 173 advantageously provide a gripping surface for an insertion instrument, thereby facilitating easy delivery of the plate to a spacer body during surgery.

FIGS. 7A-7D illustrate different views of a PEEK spacer to be used with the low profile plate shown in FIGS. 5A-5D. From these views, one can see how the spacer 110 a includes an upper surface 112 a and a lower surface 114 a with texturing 116 a; a generally C-shaped body including a pair of arms 113 a each having an inner inlet 121, 123 a formed therein; and a tapered leading edge 122 a. In addition, one skilled in the art can appreciate the substantially symmetric shape of the inner opening 120 a, which serves as a graft hole for receiving graft material therein.

FIGS. 8A-8D illustrate different views of an allograft spacer to be used with the tower profile plate shown in FIGS. 5A-5D. While the allograft spacer 110 b shares similar features to the PEEK spacer 110 a shown in previous figures, such as the C-shaped body including a pair of arms 113 b each having an inlet 121 b, 123 b formed therein, the allograft spacer 110 b need not be the same.

FIGS. 9A-9D illustrate different views of a third alternative embodiment of a low profile plate attached to a spacer according to some embodiments. In the present embodiment, the plating system 205 includes a plate 250 having lateral arms or extensions 270 that extend around an exterior surface of a spacer 210. The lateral extensions 270 extend wider than the lateral extensions 70 in the first embodiment, and do not necessarily have to interlock with the spacer 210. While in some embodiments, the plate 250 can be attached to the spacer 210 after inserting the spacer 210 into a desired location in the body, in other embodiments, the plate 250 can be pre-assembled with the spacer 210 prior to inserting the plating system 205 into the desired location.

Like the spacer 10 in FIG. 1A, the spacer 210 is configured to have an upper surface 212, a tower surface 214, and a leading end 222. In some embodiments, the upper surface 212 and/or lower surface 214 includes texturing 216, such as teeth, ribs, ripples, etc. to assist in providing frictional contact with adjacent vertebral bodies. In some embodiments, the leading end 222 of the spacer 210 can be slightly tapered, as shown in FIG. 9D. With the taper, the leading end 222 can serve as a distraction surface that helps the spacer 210 to be inserted into an intervertebral space. As shown in FIG. 9B, the leading end 222 can be slightly concave, though in other embodiments, the leading end 122 can be straight or convex. Unlike previously illustrated spacers, the spacer 210 can have a graft hole 220 that is completely enclosed. As shown in FIG. 913, the graft hole 220 can surrounded by four walls. In addition, the spacer 210 can include four outer walls: two straight walls, a convex wall and a concave wall.

In some embodiments, the graft opening 220 (shown in FIG. 9B) has a different shape from the openings of prior embodiments, as the graft opening 220 is enclosed. While the graft opening 220 is rectangular with rounded edges, in other embodiments, the graft opening 220 can have a different shape. For example, in some embodiments, the graft opening 220 can have curved walls, instead of straight walls, or can have tapered walls, instead of straight walls.

Like spacer 10, the spacer 210 can be formed of a variety of materials. In some embodiments, the spacer 210 comprises allograft bone, while in other embodiments, the spacer 210 comprises PEEK.

The plate 250 is configured to have a pair of lateral extensions 270 that receive the spacer 220. As shown in FIG. 9A, in some embodiments, the lateral extensions 270 include one or more windows 272 for improving radiolucency of the plating system. In some embodiments, the plate 250 is assembled axially to the spacer 210.

In addition to capturing the spacer 210, the plate 250 is also configured to attach into one or more vertebral bodies via one or more bone screws 88, 89. As shown in FIG. 9A, the plate 250 includes a first screw hole 252 and a second screw hole 254 for receiving bone screws 88, 89 therein. In some embodiments, screw hole 252 is angled upwardly such that an inserted bone screw 88 passes upward into an upper vertebral body, while screw hole 254 is angled downwardly such that an inserted bone screw 89 passes downward into a lower vertebral body. While the illustrated embodiment illustrates a pair of screw holes for receiving a pair of bone screws, it is possible to have one, three, four, five or more screw holes for receiving a different number of bone screws.

Over time, it is possible for bone screws to back-out. The plate 250 thus has a blocking or set screw 256 (shown in FIG. 9C) that assists in preventing back-out of inserted bone screws. As shown in FIG. 9C, the set screw 256 can be in an initial position that allows first and second bone screws to pass through holes 252, 254. Once the bone screws have been inserted through the holes 252, 254, the set screw 256 can be rotated (e.g., 90 degrees), to thereby block the bone screws and prevent back out of the bone screws. In some embodiments, the set screw 256 abuts a side of the head of the bone screws to prevent back-out of the bone screws, while in other embodiments, the set screw 256 rests over a top of the head of the bone screws to prevent back-out of the bone screws. In some embodiments, the set screw 256 comes pre-fixed with the plate 250. As shown in FIG. 9C, a single set screw 256 can be used to conveniently block a pair of bone screws. In other embodiments, each bone screw can be assigned its own set screw, which can operate independently of one another, to prevent back-out of the bone screw.

FIGS. 10A-10D illustrate different views of the low profile plate shown in FIGS. 9A-9D. From these views, one can see the lateral extensions 270 that extend from the body of the plate 250. From these views, one can also see the windows 272 (FIG. 10A) that extend along a substantial length of the lateral extensions 270. In some embodiments, each window 272 has a length greater than half the length of each lateral extension 270, thereby advantageously increasing the radiolucency of the plating system. In some embodiments, the plate 250 is assembled axially to the spacer 210.

In some embodiments, the low profile plate 250 can also include indented gripping sections 273 (shown in FIGS. 10A and 10B). These indented gripping sections 273 advantageously provide a gripping surface for an insertion instrument, thereby facilitating easy delivery of the plate to a spacer body during surgery.

FIGS. 11A-11D illustrate different views of a fourth alternative embodiment of a low profile plate attached to a spacer according to some embodiments. Like the previous embodiment, the plating system 305 includes a plate 350 having lateral arms or extensions 370 that extend around an exterior surface of a spacer 310. The lateral extensions 370 extend wider than the lateral extensions 70 in the first embodiment, and do not necessarily have to interlock with the spacer 310. While in some embodiments, the plate 350 can be attached to the spacer 310 after inserting the spacer 310 into a desired location in the body, in other embodiments, the plate 350 can be pre-assembled with the spacer 310 prior to inserting the plating system 305 into the desired location.

Like the spacer 10 in FIG. 1A, the spacer 310 is configured to have an upper surface 312, a tower surface 314, and a leading end 322. In some embodiments, the upper surface 312 and/or lower surface 314 includes texturing 316, such as teeth, ribs, ripples, etc. to assist in providing frictional contact with adjacent vertebral bodies. In some embodiments, the leading end 322 of the spacer 310 can be slightly tapered, as shown in FIG. 11D. With the taper, the leading end 322 can serve as a distraction surface that helps the spacer 310 to be inserted into an intervertebral space. As shown in FIG. 11B, the leading end 322 can be slightly concave, though in other embodiments, the leading end 322 can be straight or convex. In some embodiments, the spacer 310 can have a graft hole 320 that is completely enclosed. As shown in FIG. 11B, the graft hole 320 can surrounded by four walls. In addition, the spacer 320 can be comprised of four outer walls: two straight, one concave and one convex.

In some embodiments, the graft opening 320 (shown in FIG. 11B) of the spacer 310 is enclosed. While the graft opening 320 is rectangular with rounded edges, in other embodiments, the graft opening 320 can have a different shape. For example, in some embodiments, the graft opening 320 can have curved walls, instead of straight walls, or can have tapered walls, instead of straight walls.

Like spacer 10, the spacer 310 can be formed of a variety of materials. In some embodiments, the spacer 210 comprises allograft bone, while in other embodiments, the spacer 310 comprises PEEK.

The plate 350 is configured to have a pair of lateral extensions 370 that receive the spacer 320. As shown in FIG. 11A, in some embodiments, the lateral extensions 370 include one or more windows 372 for improving radiolucency of the plating system. In some embodiments, the plate 350 is assembled axially to the spacer 310.

In addition to capturing the spacer 310, the plate 350 is also configured to attach into one or more vertebral bodies via one or more bone screws 88, 89. As shown in FIG. 9A, the plate 350 includes a first screw hole 351, a second screw hole 352 and a third screw hole 354 for receiving bone screws 87, 88, 89 therein. In some embodiments, screw holes 352 and 354 are angled upwardly such that inserted bone screws 87, 88 pass upward into an upper vertebral body, while screw hole 351 is angled downwardly such that inserted bone screw 89 passes downward into a lower vertebral body. While the illustrated embodiment illustrates three screw holes for receiving three bone screws, it is possible to have one, two, four, five or more screw holes for receiving a different number of bone screws.

Over time, it is possible for bone screws to back-out. The plate 350 thus has blocking or set screws 356, 357, 358 (shown in FIG. 12C), each of which corresponds to one of screw holes 351, 352, 354. As shown in FIG. 12C, the set screws 356, 357, 358 can be in an initial position that allows first, second and third bone screws to pass through holes 351, 352, 354. Once the bone screws have been inserted through the holes 351, 352, 354, the set screws 356, 357, 358 can be rotated (e.g., 90 degrees), to thereby block the bone screws and prevent back out of the bone screws. In some embodiments, the set screws 356, 357, 358 abut a side of the head of the bone screws to prevent back-out of the bone screws, while in other embodiments, the set screws 356, 357, 358 rest over a top of the head of the bone screws to prevent back-out of the bone screws. In some embodiments, the set screws 356, 357, 358 come pre-fixed with the plate 350. As shown in FIG. 12C, a single set screw 356, 357, 358 can be used to conveniently block a single bone screws. In other embodiments, each set screw can be designed to block more than one set screw to prevent back-out of the bone screw.

FIGS. 12A-12D illustrate different views of the low profile plate shown in FIGS. 11A-11D. From these views, one can see the lateral extensions 370 that extend from the body of the plate 350. From these views, one can also see the windows 372 (FIG. 12A) that extend along a substantial length of the lateral extensions 370. In some embodiments, each window 372 has a length greater than half the length of each lateral extension 370, thereby advantageously increasing the radiolucency of the plating system. In some embodiments, the plate 350 is assembled axially to the spacer 310.

The plating systems describe include a plate that is independent from a spacer. The plate is low-profile and can be used with any type of spacer, such as allograft or PEEK.

FIGS. 13A-13D illustrate different views of a multi-piece allograft spacer to be used with the low profile plates discussed above according to some embodiments. The multi-piece allograft spacer 410 can be formed of an upper member 436 and a tower member 438 that are connected together via one or more pins 475. The upper member 436 and the lower member 438 each include cut-out portions that help form a graft opening 420 in the spacer 410.

The upper member 436 can include an upper surface having bone engagement surfaces (e.g., ridges, teeth, ribs) and a lower interfacing surface 446. The lower member 438 can include a tower surface having bone engagement surfaces (e.g., ridges, teeth, ribs) and an upper interfacing surface 448. In some embodiments, the upper member 436 can include one or more holes 462, while the lower member 438 can include one or more holes 464 which align with the one or more holes 462 of the upper member. The aligned holes are configured to receive one or more pins 475 to keep the upper and lower members of the allograft spacer together. In some embodiments, the pins 475 are also formed of bone material, such as allograft.

As shown best in FIG. 13C, the lower interfacing surface 446 of the upper member 436 is directly engaged with the upper interfacing surface 448 of the lower member 438. While the lower interfacing surface 446 and the upper interfacing surface 448 can be flat-on-flat, as both surfaces are planar, in some embodiments (as shown in FIG. 13C), the interface between the two surfaces is at an angle relative to the holes for receiving the pins 475. In other words, the pins 475 are received at an angle to the interface between the upper member 436 and the lower member 438. In addition, as shown in FIG. 13C, holes 462 and 464 need not go through the entirety of their respective members. For example, as shown in FIG. 13C, while hole 462 goes entirely through the upper and lower surface of the upper member 436, hole 464 goes only through the upper surface of the lower member 438, and does not go through to the lower surface. Accordingly, in some embodiments, aligned holes 462 and 464 create a “blind” pin-hole, whereby the hole does not go through the uppermost and lowermost surfaces of the spacer 410. Advantageously, in some embodiments, the use of such blind holes for receiving pins helps to maintain the pins within the spacer body.

FIGS. 14A-14D illustrate different views of an alternative multi-piece allograft spacer to be used with the tower profile plates discussed above according to some embodiments. The multi-piece allograft spacer 510 can be formed of a left member 536 and a right member 538 that are connected together in series or side-by-side (e.g., laterally) via one or more pins 575. The left member 536 and the right member 538 each include cut-out portions that help form a graft opening 520 in the spacer 510.

The left member 536 can include upper and lower surfaces having bone engagement surfaces (e.g., ridges, teeth, ribs). In addition, the left member 536 further includes a right interfacing surface 546. The right member 538 can also include upper and lower surfaces having bone engagement surfaces ridges, teeth, ribs). In addition, the right member 538 further includes a left interfacing surface 548. In some embodiments, the left member 536 can include one or more holes 562, while the right member 538 can include one or more holes 564 which align with the one or more holes 562 of the left member. The aligned holes are configured to receive one or more pins 575 to keep the left and right members of the allograft spacer together.

As shown best in FIG. 14A, the right interfacing surface 546 of the left member 536 is directly engaged with the left interfacing surface 548 of the right member 538. While the right interfacing surface 546 and the left interfacing surface 548 can be flat-on-flat, as both surfaces are planar, in some embodiments (as shown in FIG. 14A), the interface between the two surfaces is at an angle relative to the holes for receiving the pins 575. In other words, the pins 575 are received at an angle to the interface between the left member 536 and the right member 538. In addition, as shown in FIG. 14B, holes 562 and 564 need not go through the entirety of their respective members. In other words, one or more of the holes (e.g., holes 562, 564 or combined) can be blind holes, whereby the holes do not go through the left and right surfaces of the lateral implants.

By having multi-piece allograft spacers that are either stacked or aligned side-by-side, it is possible to have spacers of increased height and width. While the embodiments herein show two piece spacers, one skilled in the art will appreciate that three or more members can be combined to form multi-piece allograft spacers for use with any of the plate members described above.

FIGS. 15A-15D illustrate different views of an alternative low profile plate attached to a spacer according to some embodiments. The plating system 605 comprises a plate 650 attached or mounted to a spacer 610.

The system 605 includes a number of similar features to prior embodiments. The spacer 610 includes a body having an upper surface 612 and a lower surface 614 with texturing (e.g., ribs, grooves, teeth, protrusions) and sidewalk including one or more notches 617 for receiving plate extensions. The body of the spacer 610 can be U-shaped or C-shaped, such that a central portion includes a graft opening 620 for receiving graft material therein. The plate 650 includes a body having a first screw hole 652 for receiving a first screw member therethrough, a second screw hole 654 for receiving a second screw member therethrough, and a recess for receiving a blocking fastener or set screw 656. In addition, a pair of extension arms or members 617 extend from the plate body and are received in each of the notches 617 formed in the spacer 10. Each of the extension members 617 includes a window 672 for receiving a hump portion or region of the spacer to further secure the spacer 610 with the plate 650. In addition, the plate member 650 can include one or more stabilizers or knife-like edges 663 that can help secure the plate member 650 to a vertebral body. While the stabilizers 663 are shown as sharp and pointed, in other embodiments, the stabilizers 663 are more blunt and in some cases, even slightly rounded.

The plating system 605 in FIGS. 15A and 15D is unique in that the first upper screw hole 652 has been raised such that a central axis of the first upper screw hole 652 is positioned higher than the upper surface 612 of the spacer 610. In addition, the second lower screw hole 654 has been lowered such that a central axis of the second lower screw hole 654 is positioned below the lower surface 614 of the spacer 610. As shown in FIG. 15B, each of the holes 652, 654 has an adjacent brow member that extends from the plate body. First screw hole 652 is adjacent upper brow member 662, while second screw hole 654 is adjacent lower brow member 664. Upper brow member 662 has been raised to accommodate the raised upper screw hole 652, while lower brow member 664 has been lowered to accommodate the lowered tower screw hole 654. Advantageously, by raising the upper screw hole 652 and lowering the lower screw hole 654, this reduces the likelihood of any viewing obstruction that may occur from the spacer 610. Moreover, even though the upper brow member 662 is raised and the lower brow member 664 is lowered, advantageously, the plating system 605 still maintains a low profile such that most if not all of the plate system remains in a disc space. In other embodiments, it may be desired for a part of the upper brow member 662, a part of the lower brow member 664 or both to contact a vertebral face (e.g., an anterior face), thereby providing stability to the plating system 605.

FIGS. 16A-161) illustrate different views of a plate member 650 used in the plating system 605. From these views, one can clearly see how the upper brow member 662 and first upper hole member 652 have been raised, while the lower brow member 664 and second lower hole member 664 have been lowered, relative to other designs. In some embodiments, the entire central axis of first upper hole member 652 (e.g., from a front of the plate member 650 to a back of the plate member 650) is continuously above the upper surface of the spacer, thereby advantageously providing a less unobstructed view of the first upper hole member 652. Likewise, in some embodiments, the entire central axis of the second lower hole member 654 (e.g., from a front of the plate member 650 to aback of the plate member 650) is continuously below the lower surface of the spacer, thereby advantageously providing a less unobstructed view of the second lower hole member 654.

FIGS. 17A-17C illustrate different views of a spacer 610 used in the plating system 605. From these views, one can clearly see features of the spacer 610 includes its upper surface 612, lower surface 614, side-walls with notches 617 and graft opening 620. In addition, with the plate member removed from the views, one can also see an upper chamfer 618 a and a lower chamfer 618 b that are cut into the spacer 610. These chamfers 618 a, 618 b advantageously provide clearance for bone screws that are inserted through the plating system 605. One skilled in the art will appreciate that the spacer can be made of many different materials. In some embodiments, the spacer will be made out of bone (e.g., allograft), while in other embodiments, the spacer will be made of PEEK. Advantageously, the plating system 605 is removably attached to the spacer 610 such that a surgeon can choose to include a spacer of a certain material as so desired during a surgical procedure.

FIGS. 18A-18D illustrate different views of yet another plate system involving a plate member and a spacer having a unique multi-piece composition in accordance with some embodiments. The plate system 705 includes similar elements as found in prior embodiments, including a plate member 750 having a first upwardly oriented screw hole 752 for receiving a first screw, a second downwardly oriented screw hole 754 for receiving a second screw, and a blocking member or screw 756, as well as a spacer 710 allograft or PEEK) having an upper surface 712, a tower surface 714, a graft opening 720, and notches 717 for receiving arms or extensions 770 of the plate member 750. The plate member 750 also includes one or more windows 772 in its extensions 770 for receiving a raised or bump out portion of the spacer 705, thereby helping to retain the spacer 705 within the plate member 750. In addition, the plate member 750 includes stabilizers 763 in the form of knife-like edges that help to grip into a vertebral body.

In addition to these features, the spacer 710 has a unique multi-piece composition. As shown in FIGS. 18A and 18D, in some embodiments, the spacer 710 has a body formed of two adjacent members—a first member 711 and a second member 713. The first member 711 and the second member 713 can be held together via one or more pin members, although in other embodiments, the first member 711 and second member 713 can be held via adhesive, mateable connections, etc. As shown in FIG. 18D, second member 713 can include an upper overhang region 717 that hangs over a part of the first member 711. Similarly, first member 711 can include a lower overhang region 711 that hangs below a part of the second member 713. Advantageously, these overhang regions 711 serve as guides to identify the location of the interface 715 between the first member 711 and the second member 713. During manufacturing, the overhang regions 711 make it easy to inspect the interface to 715 to ensure that the two members 711, 713 are properly secured together. While the illustrated embodiment shows a spacer 710 having two separate overhanging regions, in other embodiments, the spacer 710 can have one single overhanging region. As before, the spacer 710 can be made of many different types of materials, including bone (e.g., allograft) and PEEK), and a surgeon can advantageously decide what type of spacer should accompany the plate before or during surgery.

FIG. 19 shows a plating system 805 having a plate member 850 having extensions 870 and a spacer 810 similar to that found in FIGS. 18A-18D; however, the spacer 810 is designed to accommodate lordosis. In other words, while the upper surface 712 and lower surface 714 of the spacer 710 can be substantially parallel (as shown in FIG. 18C), the upper surface 812 and lower surface 814 of the spacer 810 can have some degree of angulation or lordosis. In some embodiments, relative to a mid-line of the spacer 810, the upper surface 812 and/or lower surface 814 can have a degree of angulation of 2, 3, 5, 7, 12 degrees or more. Advantageously, the lordotic spacer 810 (which is accompanied with the plate member 850) helps to accommodate different anatomies.

FIGS. 20A-20D show yet another alternative plating system having a plate member attached to multiple spacers in accordance with embodiments of the present application. The unique plating system 905 comprises a plate member 950 having a pair of inner arms or extensions 975 and a pair of outer arms or extensions 970 for receiving one or more spacers 910 therein. In some embodiments, both the inner and outer extensions 975, 970 include protruding portions designed to be received in notches in the one or more spacers.

As shown in FIG. 20A, the plating system 905 includes a first spacer 910 a that is retained between a shorter outer extension 970 and a longer inner extension 975 of the plate member 950. The shorter outer extension 970 of the plate is configured to be received in notch 917 of the spacer 910 a, while the longer inner extension 975 of the plate is configured to be received in notch of the spacer 910 a. In addition, advantageously, the shorter outer extension 970 includes a window 972 and the longer inner extension 975 includes a window 974. Each of the windows 972, 974 is configured to receive a bump out portion of the spacer 910, thereby helping to retain the spacer 910 to the plate member 905. In addition, the windows 972, 974 help to provide a means to visualize fusion (e.g., in a lateral image) that is occurring once the spacer is implanted within a disc space. Similarly, the plating system 905 includes a second spacer 910 b that is retained between a shorter outer extension 970 and a longer inner extension 975 on an opposite side of the plate member 950. While in the present embodiment, each of the longer inner extensions 975 is separated from the other without any connecting member, in other embodiments, a connection bar or bridge (such as shown in FIGS. 21A and 21B) can extend between the two inner extensions 975. Advantageously, when the plating system 905 is placed in a disc space, graft material can be packed between the two inner extensions 975 to promote fusion within the disc space.

Advantageously, in accordance with some embodiments, the plating system 905 is designed to hold at least two spacers 910 a, 910 b. In some embodiments, the spacers 910 a, 910 b are substantially rectangular pieces. In some embodiments, the spacers 910 a, 910 b can have substantially rounded edges. In some embodiments, the spacers 910 a, 910 b can include one or more chamfers 918 for providing clearance for one or more screws that are inserted through the plate member 905. For example, spacer 910 a can include a chamfer that provides clearance for a screw that passes through plate opening 954, while spacer 910 b can include a chamfer that provides clearance for a screw that passes through plate opening 952. Advantageously, the use of two spacers 910 a, 910 b—one on each side of the plate system 905—helps to stabilize the plate system within the disc space. Moreover, having multiple individual spacers 910 a, 910 b that are smaller in size can ease manufacturing issues, as the spacers can be formed of relatively small pieces of bone, which can be easier to find than larger pieces of bone. In other words, bone that is removed from a body can improve the yield of production, as it will be easier to create the spacer members. While the spacers 910 a, 910 b are illustrated as being single-bodied members in the present embodiments, in other embodiments, the spacers can be formed of multiple pieces (e.g., pinned together).

FIGS. 21A and 21B illustrate different views of another alternative low profile plate attached to multiple spacers according to some embodiments. The plate system 1005 comprises a plate member 1050 attached to a pair of spacers 1010 a and 1010 b. Like the embodiment in FIG. 20A, the plate member 1050 of the present embodiment includes a pair of outer arms or extensions 1070 a, 1070 b and a pair of inner arms or extensions 1075 a, 1075 b. Plate extensions 1070 a and 1075 a are configured to retain spacer 1010 a, while plate extensions 1070 b and 1075 b are configured to retain spacer 10101). As shown in FIGS. 21A and 21B, the inner extensions 1075 a and 1075 b includes a connection or bridge member 1088 that extends between them. Advantageously, the bridge member 1088 helps provide added stability to the plate system 1005, and also helps provide a barrier to retain graft material within the plate system 1005. As shown in FIG. 21A, in some embodiments, the inner extensions 1075 a and 1075 b are parallel to one another.

As shown in FIG. 21B, outer plate extensions 1070 a and 1070 b include at least one window 1072 formed therein. Similarly, inner plate extensions 1075 a and 1075 b include at least one window formed therein. As shown in FIG. 21B, inner plate extensions each include two windows—1074 and 1075—that are formed adjacent to one another Inner plate extension 1075 a includes windows 1074 a and 1075 a, while inner plate extension 1075 b includes windows 1074 b and 1075 b. In some embodiments, the windows 1072, 1074, 1075 can advantageously be designed to hold a bump out portion of the spacers and/or provide increased visualization to a surgeon during or after a fusion procedure. While in some embodiments, each of the windows 1072, 1074, and 1075 perform the same duties and functions, in other embodiments, the windows can perform different functions. For example, while inner window 1074 can be used to both retain the spacer and aid in fusion visualization, inner window 1075 can be used simply for fusion visualization.

FIG. 22 illustrates another alternative low profile plate attached to multiple spacers according to some embodiments. The plate system 1105 comprises a plate member 1150 attached to a pair of spacers 1110 a and 1110 b. Like the embodiment in FIG. 21A, the plate member 1150 of the present embodiment includes a pair of outer arms or extensions 1170 a, 1170 b and a pair of inner arms or extensions 1175 a, 1175 b. Plate extensions 1170 a and 1175 a are configured to retain spacer 1110 a, white plate extensions 1170 b and 1175 b are configured to retain spacer 1110 b. As shown in FIGS. 21A and 21B, the inner extensions 1175 a and 1175 b includes a connection or bridge member 1188 that extends between them. Advantageously, the bridge member 1188 helps provide added stability to the plate system 1105, and also helps provide a barrier to retain grail material within the plate system 1105. In contrast to the inner extensions 1075 a, 1075 b FIG. 21A, the inner extensions 1175 a, 1175 b are non-parallel and angulated relative to one another. Furthermore, due to the shape of the plate member 1150, the shapes of the individual spacers 1110 a and 1110 b differ in that they have a prominent angled surface adjacent to the inner extensions 1175 a, 1175 b.

FIG. 23 illustrates another alternative low profile plate attached to multiple spacers according to some embodiments. The plate system 1205 comprises a plate member 1250 attached to a pair of spacers 1210 a and 1210 b. Like the embodiment in FIG. 22, the plate member 1250 of the present embodiment includes a pair of outer arms or extensions 1270 a, 1270 b and a pair of inner arms or extensions 1275 a, 1275 b. Plate extensions 1270 a and 1275 a are configured to retain spacer 1210 a, white plate extensions 1270 b and 1275 b are configured to retain spacer 1210 b. As shown in FIG. 23, the inner extensions 1275 a and 1275 b includes a connection or bridge member 1288 that extends between them. Advantageously, the bridge member 1288 helps provide added stability to the plate system 1205, and also helps provide a barrier to retain graft material within the plate system 1205. In contrast to the bridge member 1188 in FIG. 22, the bridge member 1288 is elongated and extends to a distal end of the spacers 1210 a, 1210 b, thereby creating an even larger space for receiving graft material in the middle of the plate system 1205.

FIGS. 24A-24C illustrate another alternative low profile plate attached to multiple spacers according to some embodiments. The plate system 1305 comprises a plate member 1350 attached to a multi-piece spacer 1310 formed of three members 1310 a, 1310 b, 1310 c. Like the embodiment in FIG. 23, the plate member 1350 of the present embodiment includes a pair of outer arms or extensions 1370 a, 1370 b and a pair of inner arms or extensions 1375 a, 1375 b connected by a bridge member 1388. The inner extensions 1375 a, 1375 b and bridge member 1388 are configured to be enclosed by the body of the spacer 1310. Advantageously, the bridge member 1388 helps provide added stability to the plate system 1305, and also helps provide a barrier to retain graft material within the plate system 1305.

In some embodiments, the spacer 1310 is formed of three different members 1310 a, 13110 b, 1310 c. The members 1310 a and 13110 b can be outer members which bound the inner member 1310 c. As shown in FIG. 24C, the members 1310 a and 1310 b can be substantially similar, and can include upper and tower surfaces with surface protrusions to enable better gripping of bone. Inner member 1310 c can be different from the other members and can include a relatively smooth surface without surface protrusions. In addition, the inner member 1310 c can be of a different height than the other members. In some embodiments, the three members 1310 a, 1310 b, 1310 c are pinned together, while in other embodiments, they can be joined together via an adhesive or mateable connection. Advantageously, the addition of the inner member 1310 c provides further support to the overall structure of the plate system 1305.

FIGS. 25A and 25B illustrate another alternative low profile plate attached to a multi-piece spacer having a metal insert according to some embodiments. The plate system 1405 comprises a plate member 1450 attached to a multi-piece spacer 1410 formed of two similar components 1410 a, 1410 b and a metal insert 1439. The plate member 1450 can include a first screw opening, a second screw opening and a rotatable locking mechanism 1456 to prevent back out of screws that are inserted through the openings. In some embodiments, the plate member 1450 of the present embodiment is mounted to the front of the spacer. In other embodiments, the plate member 1450 includes a pair of outer arms or extensions and/or a pair of inner arms or extensions (not shown) to help retain the spacer 1410 within the plate member 1450.

In some embodiments, the spacer 1410 is formed of two members 1410 a and 1410 b separated by a metal insert 1439. These members partially enclose a graft opening 1420. The two members 1410 a and 1410 b can be formed of a material different from the metal insert 1439, such as PEEK. Advantageously, the metal insert 1439 is designed to provide additional strength to the spacer 1410. In some embodiments, the metal insert 1439 is formed of titanium. As shown in the exploded view in FIG. 25B, the spacer 1410 be attached to the plate member 1450 via vertical fastening members 1429 a, 1429 b. One skilled in the art will appreciate that the spacer 1410 can be used with any of the other plate members discussed above.

One skilled in the art will appreciate that any of the plate systems described above can be used with other spinal implants. Among the other implants that can accompany the plate systems include stabilization systems and rod systems, including rod members, hook members, and bone fasteners such as pedicle screws. One skilled in the art will appreciate that any of the plate systems described above can also be used with one another, or can be used multiple times along different segments of the spine. In addition, any of the plate systems described above can be used with a variety of navigation and guidance tools, including those related to neuromonitoring and robotics. Furthermore, one of skill in the art will appreciate that the plate systems described above can be produced in a number of different ways, including in part via 3-D printing methods.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. Moreover, the improved plate systems and bone screw assemblies and related methods of use need not feature all of the objects, advantages, features and aspects discussed above. Thus, for example, those skilled in the art will recognize that the invention can be embodied or carried out in a manner that achieves or optimizes one advantage or a group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein. In addition, while a number of variations of the invention have been shown and described in detail, other modifications and methods of use, which are within the scope of this invention, will be readily apparent to those of skill in the art based upon this disclosure, it is contemplated that various combinations or subcombinations of these specific features and aspects of embodiments may be made and still fall within the scope of the invention. Accordingly, it should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the discussed bone screw assemblies. Thus, it is intended that the present invention cover the modifications and variations of this invention provided that they come within the scope of the appended claims or their equivalents. 

What is claimed is:
 1. A spinal system comprising: a plate member comprising a body having a curved front surface and first and second outer extensions, wherein the plate member includes a first screw hole for receiving a first bone screw and a second screw hole for receiving a second bone screw, wherein the first screw hole is oriented in an upward direction and the second screw hole is oriented in a downward direction, and a rotatable blocking mechanism designed to block at least a portion of the first screw hole and the second screw hole to prevent backout of the first bone screw and the second bone screw; a first bone screw insertable through the first screw hole; a second bone screw insertable through the second screw hole; and at least one spacer received within the plate member, wherein the spacer includes an upper surface and a tower surface and an axis that extends between the upper surface and the lower surface, wherein the upper surface includes surface protrusions for contacting an upper vertebral member and the lower surface includes surface protrusions for contacting a lower vertebral member, wherein in a direction along the axis that extends between the upper surface and the lower surface of the at least one spacer, the first screw hole of the plate member has a central axis that extends completely above the upper surface of the at least one spacer and the second screw hole of the plate member has a central axis that extends completely below the lower surface of the at least one spacer.
 2. The spinal system of claim 1, wherein the plate member includes first and second inner extensions.
 3. The spinal system of claim 2, wherein the first and second inner extensions are longer than the first and second outer extensions.
 4. The spinal system of claim 2, wherein the first and second inner extensions are connected via a connecting member.
 5. The spinal system of claim 2, further comprising a first spacer and a second spacer, wherein the first spacer is received between the first outer extension and the first inner extension and the second spacer is received between the second outer extension and the second inner extension.
 6. The spinal system of claim 1, wherein the at least one spacer is formed of three components.
 7. The spinal system of claim 6, wherein the three components include two bone members and a metal insert.
 8. The spinal system of claim 7, wherein the metal insert is formed of titanium.
 9. The spinal system of claim 1, further including a stabilization system for accompanying the plate member, wherein the stabilization system includes a plurality of rod members and a plurality of screw members.
 10. A spinal system comprising: a plate member comprising a body having a front surface and first and second outer extensions and first and second inner extensions, wherein the plate member includes a first screw hole for receiving a first bone screw and a second screw hole for receiving a second bone screw, wherein the first screw hole is oriented in an upward direction and the second screw hole is oriented in a downward direction, and a blocking mechanism designed to prevent backout of the first bone screw and the second bone screw; a first bone screw insertable through the first screw hole; a second bone screw insertable through the second screw hole; a first spacer operably attached to the plate member, wherein the first spacer comprises an upper surface and a tower surface, and wherein the first spacer is received between the first inner extension and the first outer extension; and a second spacer operably attached to the plate member, wherein the second spacer comprises an upper surface and a lower surface, and wherein the second spacer is received between the second inner extension and the second outer extension.
 11. The spinal system of claim 10, wherein in a direction along the axis that extends between the upper surface and the tower surface of the first spacer, the first screw hole of the plate member has a central axis that extends completely above the upper surface of the at least one spacer and the second screw hole of the plate member has a central axis that extends completely below the lower surface of the at least one spacer.
 12. The spinal system of claim 10, wherein the first spacer and the second spacer are both formed of allograft bone.
 13. The spinal system of claim 10, wherein at least one of the first spacer and the second spacer includes a chamfer.
 14. The spinal system of claim 10, wherein the first and second inner extensions are connected to one another via a bridge portion.
 15. The spinal system of claim 14, wherein the bridge portion is positioned adjacent a distal end of the first spacer and a distal end of the second spacer.
 16. The spinal system of claim 10, wherein the first outer extension includes a protrusion that is received in a notch formed in the first spacer.
 17. The spinal system of claim 16, wherein the first inner extension includes a protrusion that is received in a different notch formed in the first spacer.
 18. The spinal system of claim 10, wherein the first and second inner extensions are parallel to one another.
 19. The spinal system of claim 10, wherein the first and second inner extensions are non-parallel to one another.
 20. The spinal system of claim 10, further including a stabilization system for accompanying the plate member, wherein the stabilization system includes a plurality of rod members and a plurality of screw members. 